HI-VOLUME oil pump

[87 national]

should i order a high volume or just stick with the stock my motor does have some mod like 66 turbo and some one has been in the motor with upgrades. what do you suggest? thanks

 

[turbofabricator]

I would NOT suggest using a hi-volume pump on just about any engine. If you control the oil leaks during engine assembly, there is no need for one. The stock pump, albeit very primative, works great. I keep the pump cover to gear face clearance as close to .0005-.0015 as I can. (half a thou. to one and a half thou.) I radius all the passages in the cover AND block, keep bearing clearances to .0017"-.0019", rotate cam bearing oil feed holes so they are partially blocked (you can drill new .050-.098" holes if you like, and rotate the original feed hole away from the passage) and you can even reduce the pushrod feed holes if you run roller rockers. (though probably not worth the effort) Good remote oil filtration system will help, too. But,......a completely stock oiling system is adaquate for more than 500hp. So, unless you are a extremely technical guy like me, leave it stock, and keep the bearing clearances tight. Oh, ya, leave the oil pressure gauge in the garage, too. That way when the pressure drops to >15psi at hot idle, you won't freak-out. Nothing wrong with only 10 psi of hot idle oil pressure. As long as it jumps to 40+ psi at throttle tip-in.

 

[pajo]

x

x2:biggrin:

 

[GSTOY]

Do the Earl Brown oil mods and you won't look back. I have 30~35 Psi hot in drive and 65+ driving around on stock oil pump with earl brown mods. Do a search and you will find everything you need to know. Well worth the time to perform. Oh yea x3 on above advice.

 

[DougsfastZ]

I did what Earl Brown wrote up to my stock front cover. I see about 25 psi at temp in gear running 15w40 Rotella and a Delco filter.

I'm happy with the results so far.

 

[DR BOOST]

I would NOT suggest using a hi-volume pump on just about any engine. If you control the oil leaks during engine assembly, there is no need for one. The stock pump, albeit very primative, works great. I keep the pump cover to gear face clearance as close to .0005-.0015 as I can. (half a thou. to one and a half thou.) I radius all the passages in the cover AND block, keep bearing clearances to .0017"-.0019", rotate cam bearing oil feed holes so they are partially blocked (you can drill new .050-.098" holes if you like, and rotate the original feed hole away from the passage) and you can even reduce the pushrod feed holes if you run roller rockers. (though probably not worth the effort) Good remote oil filtration system will help, too. But,......a completely stock oiling system is adaquate for more than 500hp. So, unless you are a extremely technical guy like me, leave it stock, and keep the bearing clearances tight. Oh, ya, leave the oil pressure gauge in the garage, too. That way when the pressure drops to >15psi at hot idle, you won't freak-out. Nothing wrong with only 10 psi of hot idle oil pressure. As long as it jumps to 40+ psi at throttle tip-in.

the perfect answer

 

[buickgn87]

I have the hi-vol cover and pump on my engine.
It has 10-15 hot idle and 40-50 at highway speeds.

Should I replace the front cover/pump with a stock one?

 

[Red Regal T]

should i order a high volume or just stick with the stock my motor does have some mod like 66 turbo and some one has been in the motor with upgrades. what do you suggest? thanks

I've been running HV oil pumps for 25 years. Never had a problem. I like 'em. If it doesn't bother you to have the adequate 10 psi at idle, then just go with the stocker. I have stock pump on my T. With 20W50 I have 10 at idle, hot. On my GN I have a high volume, and with 10W40 oil I have 25-30 at idle. I think I'm happier with my GN's oil pressure.

I don't know how many miles on your motor. Maybe you need to check the bearings. Not too hard to slap in a new set.

 

[turbobitt]

I have the hi-vol cover and pump on my engine.
It has 10-15 hot idle and 40-50 at highway speeds.

Should I replace the front cover/pump with a stock one?

The biggest issue with the high volume covers, or any of the aftermarket covers is that the internal passages are not sufficient to carry the extra volume that the gears are capable of moving. This is where the internal pump pressure is probably much higher then the oil galley pressure resulting in extra load on the gears. If a high volume pump is going to be used, then it must be ported and modified like the Earl Brown mods.
Allan G.

 

[earlbrown]

Just to throw out a little fun math for you....


It's pretty common knowledge not to drill out aftermarket covers to 1/2". From what I've gathered I understand they like to either blow out the side or vent to the adjacent bolt hole. (I can't say first hand as I'd never consider putting one on my personal car).


The area of a 1/2" hole is .196 square inches. The area of a 7/16" hole (which I think aftermarkets and stock untouched covers are) is .150 square inches.

The PSI readings that everyone likes to use as a benchmark is relative to square inches. Using that as a gauge, the 1/2 hole will flow 133% more oil at the same pressure. (that's on paper not accounting for frictional losses and such)

Now lets look at the stock untouched Buick oiling system with no mods.....


Let's say you have house pressure with a nice even 100PSI in the pipes and your front yard is on fire. With a normal sized garden hose you're going to flow X amount of water and put the fire out in a certain amount of time.

Now your neighbor has 133PSI but his garden hose flows 3/4's that of yours......


Who's going to have the highest gauge reading?

Yet who's going to put the fire out faster?

and Who's going to have pipes that are less stressed?

 

[turbobitt]

Just to throw out a little fun math for you....


It's pretty common knowledge not to drill out aftermarket covers to 1/2". From what I've gathered I understand they like to either blow out the side or vent to the adjacent bolt hole. (I can't say first hand as I'd never consider putting one on my personal car).


The area of a 1/2" hole is .196 square inches. The area of a 7/16" hole (which I think aftermarkets and stock untouched covers are) is .150 square inches.

Don't know exactly how large they can go but I can tell you that they core the holes when they cast the covers and they are not machined. As a result, there is significant draft in the holes. The oil feed hole at the pump cover gasket surface starts out near gasket size and tappers to almost nothing near the 90 degree intersect at the engine gasket interface. The same is true in the oil suction ports.
I finished modifying a new HV cover for my stage engine a few months ago. Although I'm happy with the results, it did take considerable work to make it right, And a huge pile of aluminum chips.
Allan G.